The present invention relates in general to medical instruments suitable for endoscopic or laproscopic applications, and capable of passing through a trocar or similar device. More specifically, the present invention relates to a novel hydraulically actuated medical instrument suitable for stapling or other desired endoscopic or laproscopic applications.
Surgical instruments, such as staplers, graspers, scissors, coagulators and the like, suitable for endoscopic or laproscopic applications in which the device is inserted through a cannula or trocar, are well known. As described in more detail below, the present invention, in its most preferred embodiment, is directed to an endoscopic stapler particularly suited for minimally invasive surgery, such as for isolating the left atrial appendage on human hearts. Such procedures are described in U.S. Pat. No. 5,306,234, and U.S. patent application Ser. No. 09/315,601, filed on May 20, 1999 to Aaron V. Kaplan, both of which are incorporated by reference herein.
Also, endoscopic medical instruments are often of complicated construction, especially when the instrument is articulated to allow the handle and/or end effector to pivot or rotate. Typically, a mechanical linkage extends between the handle and end effector to allow operator actuation of the end effector. When the instrument is of the type that permits articulation, the mechanical linkage must accommodate the articulation. This often results in a design that is relatively complicated, that is costly to manufacture and/or that may still experience limitations regarding the degree or direction of articulation.
The mechanical linkage also may limit the shape, or configuration of the shaft and/or the ability of the shaft to be flexible so as to navigate a path within the body cavity during the medical procedure.
Other complications of a mechanical linkage may also arise relative to the shape and configuration of the end effector. The mechanical linkage must interface with the end effector so as to permit relative movement of the jaws in addition to driving of the staples. This can result in a complex attachment between the end effector and mechanical linkage that is expensive to make and difficult to assemble.
The present invention may be generally embodied in a hydraulically actuated medical device of a type suitable for endoscopic or laproscopic procedures and which includes, in one embodiment, an elongated shaft having a proximal end and a distal end, an end effector at the distal end of the elongated shaft, a handle portion at the proximal end of the elongated shaft, and a fluid flow path extending between the handle and the end effector.
In accordance with one aspect of the present invention, the end effector is elongated and at least a portion of the end effector extends at an angle to another portion of the end effector to make the end effector suitable for particular procedures. For example, the end effector may be continuously curved along its length so as to contact the tissue that is being stapled or otherwise treated in an arc. Any curved configuration of the end effector, such as lateral, vertical or complex, is contemplated by the present invention and intended to be within the above reference to one portion of the end effector extending to an angle to another portion. Also, the end effector may have at least two straight portions, one of which extends at a fixed or variable angle to the other portions.
It is possible for the end effector to be flexible along its entire length or a portion thereof and/or to employ suitable inner malleable shape-retaining elements. The end effector may be made of any polymer or metallic substance or other suitable materials as well as a combination thereof. The end effector is preferably preformed to exhibit a desired configuration corresponding to a specific medical procedure.
In accordance with another aspect of the present invention, at least a portion of the shaft may be flexible so that the shaft may be manually configured into a particular non-straight shape (such as a curved, offset, fixed or variable angle), which one portion of the shaft extends at an angle relative to another portion. The shaft may be flexible along its entire length or a substantial portion thereof to provide for a variety of shapes and configurations of the shaft, as will be described below.
In accordance with a further aspect of the present invention, the elongated shaft may include a flexible outer shaft having at least one inner hydraulic fluid flow path extending between the handle portion and the end effector through the elongated shaft. At least a portion of the shaft is manually movable to a direction in which it extends at an angle to another portion of the shaft. It is contemplated that numerous shapes and configurations of the shaft are possible and may depend on the particular medical procedure employed, the area of the body involved in the medical procedure, and the method of approach utilized as well as other factors.
The shaft may be flexible along its entire length or any portion thereof. The shaft may be resilient, have shape retaining characteristics or it may be capable of freely conforming to the shape configuration of the pathway defined by its surroundings such as, for example, a trocar, introduction sleeve or a channel defined within the patient. Where the shaft is capable of shape retention, the shape and configuration of the shaft may be deformed, for example, manually by the operator, and the shape is retained until repositioned or, alternately, via control wires extending from the handle, through the shaft which can control the direction, shape and configuration of the shaft.
The shaft may be comprised of a suitable plastic polymeric material, metal, other suitable materials or a combination thereof. The material may also be manufactured into a preformed configuration using heat-forming techniques such as, for example, thermoforming which allows a shaft made of plastic in part or in whole to be preformed into a particular shape or corresponding to a specific medical procedure. Other methods may also be used, such as conventional shape forming methods, to form metallic materials into a particular shape. The outer shaft also may have a generally fluted, accordion, corrugated or undulating shape-retaining surface.
In another aspect of the present invention the shaft may be comprised of an outer flexible shaft and an inner metallic element extending along the shaft between the handle portion and the end effector. The inner malleable element preferably is capable of shape retention and can be manually moved or deformed into a desired configuration where at least a portion of the shaft extends at an angled direction relative to another portion of the shaft. Manual movement allows deflection or angling of the shaft along one or more portions of the shaft and is preferably provided at the distal portion of the shaft which is inserted into the patient""s body. Manual movement can be effectuated in one or more planes relative to the longitudinal axis of the shaft. The shape and configuration of the shaft may be set, for example, directly by hand or indirectly using control rods. It is contemplated that the metallic element may be in the form of, for example, a metal rod, a spiral wound wire, as well as other malleable shape retention members or configurations.
Other features and aspects of the present invention are set forth in the following detailed description and claims.